CV 7 Flashcards
What do you give to treat angina and MIs?
Nitroglycerine
Repolarization abnormalities are a sign of what?
Ischemia and heart attacks
Like a flipped T wave
ST changes are a sign of what?
Ischemia and heart attacks
4 factors that influence CO
2 cardiac factors, 2 coupling factors
Cardiac: HR and myocardial contractility
Coupling: Preload and afterload
Where is the wall stress greatest?
Subendocardium
inner wall
3 causes of LV concentric hypertrophy
Exercise
Hypertension
Aortic valve stenosis
What do leads 1, 2 and 3 look like normally?
All have positive deflections
Lead 2 has the largest positive deflection
Arrow points to 60 degrees (bottom right)
What do leads 1, 2 and 3 look like in Right axis shift?
Lead 1 has negative deflection
Lead 2 positive but smaller than normal
Lead 3 large and positive
Arrow will be pointing to the bottom left (120 deg)
What do leads 1, 2 and 3 look like in Left axis shift?
Lead 1 is large and positive
Lead 2 is small and positive
Lead 3 is negative
Arrow points to 0 or upper right
What physical changes cause left or right axis shift?
LV hypertrophy (left axis) RV hypertrophy (right axis)
From ECG, how would you tell there is LV hypertrophy
Add V1 with either V5 or V6
If it’s over 35 mm (35 squares), then there is hypertrophy
Why would you get increased QRS interval and increased R wave amplitude in hypertrophy?
Would take longer to depolarize more muscle
More tissue to move through means stronger signal
